He's had more comebacks than the proverbial boomerang, so much so, he's been dubbed The Comeback Kid but ask John Travolta what he makes of his yo-yo career and he looks genuinely bemused.

"You know what I was never aware of it," he says. "Kirstie Alley, who I worked with, told everyone that I was never aware of having cooled off and it's true. Until I got hired for Pulp Fiction I didn't know I had cooled off. Maybe it was self-protection I don't know."

Even if Travolta is blissfully unaware of his movie-making highs and lows, his adoring fans aren't. He may have put the odd toe-tapping foot wrong since he burst on the scene strutting his stuff in the 1977 Saturday Night Fever, but he's always welcomed back from the movie wilderness with open arms.

That's probably because Travolta has a reputation in the business for being a true gentleman and one of the nicest stars around. Happily, meeting him in the flesh, confirms that really is the case.

Striding into the room, all 6ft 2ins of him. Travolta has that rare thing, genuine movie-star charisma - in bucket loads. At 47-years old he's heavier than his svelte-like Saturday Night Fever days, but the penetrating blue eyes are as sparkling as ever and there's still a full head of coal black hair.

So, how does he really feel about the constant references to his fluctuating size and career?

"I love it," he says with a broad grin. "The more they talk about my comebacks and my gaining weight and my losing weight, that's great. I've been around to long to worry about it."

Born to a large Italian-Irish family in Englewood, New Jersey, Travolta has been on the acting scene for most of his adult life. He first gained success in America in the TV series Welcome Back Kotter but it was at the age of 24, that he became an international superstar with Saturday Night Fever, followed a year later by the box office hit Grease.

But as quickly as he gained his superstar status he lost it with the flop 1978 movie Moment By Moment. Travolta spent the next decade appearing in unmemorable offerings until he found himself back at the top again with his Oscar-nominated role in Quentin Tarantino's Pulp Fiction.

Since then it's been a roller-coaster ride of major hits (Primary Colors, Face/Off) and spectacular misses (Battlefield Earth). But he's back on fighting form again with his latest movie Swordfish, a cyberspace terrorist thriller also starring Halle Berry and Australian Hugh Jackman.

In the film, which opens here this week, Travolta plays Gabriel Shear, the world's most dangerous man, who attempts to steal billions of pounds in illegal government funds, with the help of a superhacker (Jackman).

Travolta's performance in the explosive thriller has received plenty of praise from the critics but he admits his computer whizkid role required some serious acting skills.

"I am not at all computer literate in real life," he smiles. "I haven't yet found a reason to be. Once I find a reason why I need to be on the Internet then I will be."

The movie has already gained plenty of publicity as it features a topless Halle Berry. The actress admits she was nervous about the scene but Travolta had no such reservations.

"When I found out about it I made a beeline for the set," he says with an uproarious laugh. In fact he was so impressed with the stunning actress he asked the crew for a round of applause in appreciation of her body.

However, his wife, actress Kelly Preston needn't worry. The couple, are thought to have one of the most solid marriages in showbusiness and Travolta is refreshingly down to earth about the secret of their success.

"Mostly it's the motivation of not wanting to be single. That helps a lot," he laughs, before adding seriously. "We believe in communication and we use that to solve problems."

The pair, who met on the 1989 movie The Experts, have two children Jett, nine, and Ella Bleu, one and Travolta insists he's never separated from his family for too long.

"They come with me on location and I have it written into my contract that I will be done every day by 6pm no matter what," he explains, "By that time Jett is home from school. We sit down, turn off the phone and have our quality time. I can't tell you how much I treasure that."

With a fee of 20 million dollars a movie, Travolta could afford to have as much quality time as he likes with the family but the versatile star has no intention of disappearing from view again.

He says he has one big ambition left - to appear in another big screen musical. However, it won't be in the much talked about movie adaptation of the stage show Chicago.

"It's been offered to me three times," he reveals, "But I don't know how it would translate into a movie. Pissed off hookers that's what it's about. I don't know how that would work, on the big screen." he grins.